﻿# Importing stuff
from ctypes import *
from glpk import *

if __name__ == '__main__':

    # allocating some variables
    ia = (c_int*(1+1000))(); ja = (c_int*(1+1000))();
    ar = (c_double*(1+1000))();
    lp = glp_create_prob();
    glp_set_prob_name(lp, "sample");
    glp_set_obj_dir(lp, GLP_MAX);
    glp_add_rows(lp, 3);
    glp_set_row_name(lp, 1, "p");
    glp_set_row_bnds(lp, 1, GLP_UP, 0.0, 100.0);
    glp_set_row_name(lp, 2, "q");
    glp_set_row_bnds(lp, 2, GLP_UP, 0.0, 600.0);
    glp_set_row_name(lp, 3, "r");
    glp_set_row_bnds(lp, 3, GLP_UP, 0.0, 300.0);
    glp_add_cols(lp, 3);
    glp_set_col_name(lp, 1, "x1");
    glp_set_col_bnds(lp, 1, GLP_LO, 0.0, 0.0);
    glp_set_obj_coef(lp, 1, 10.0);
    glp_set_col_name(lp, 2, "x2");
    glp_set_col_bnds(lp, 2, GLP_LO, 0.0, 0.0);
    glp_set_obj_coef(lp, 2, 6.0);
    glp_set_col_name(lp, 3, "x3");
    glp_set_col_bnds(lp, 3, GLP_LO, 0.0, 0.0);
    glp_set_obj_coef(lp, 3, 4.0);
    ia[1] = 1; ja[1] = 1; ar[1] = 1.0; # a[1,1] = 1
    ia[2] = 1; ja[2] = 2; ar[2] = 1.0; # a[1,2] = 1
    ia[3] = 1; ja[3] = 3; ar[3] = 1.0; # a[1,3] = 1
    ia[4] = 2; ja[4] = 1; ar[4] = 10.0; # a[2,1] = 10
    ia[5] = 3; ja[5] = 1; ar[5] = 2.0; # a[3,1] = 2
    ia[6] = 2; ja[6] = 2; ar[6] = 4.0; # a[2,2] = 4
    ia[7] = 3; ja[7] = 2; ar[7] = 2.0; # a[3,2] = 2
    ia[8] = 2; ja[8] = 3; ar[8] = 5.0; # a[2,3] = 5
    ia[9] = 3; ja[9] = 3; ar[9] = 6.0; # a[3,3] = 6
    glp_load_matrix(lp, 9, ia, ja, ar);
    glp_simplex(lp, None);
    Z = glp_get_obj_val(lp);
    x1 = glp_get_col_prim(lp, 1);
    x2 = glp_get_col_prim(lp, 2);
    x3 = glp_get_col_prim(lp, 3);
    print "\nZ = %g; x1 = %g; x2 = %g; x3 = %g\n" % (Z, x1, x2, x3);
    glp_delete_prob(lp);
